Question

Quadratic equation plz solve very urgent

Answer 1

$5x {}^{2} - 8x - 4 = 0 \\ 5x {}^{2} - 10x + 2x - 4 = 0 \\ 5x(x - 2) + 2(x - 2) = 0 \\ (5x + 2)(x - 2) = 0 \\ x = - 2 \div 5or \: x = 2 \\ hope \: it \: will \: help \: you$

Answer 2

Hey there!

Solving it by applying quadratic formula for equation "5x^2 - 8x - 4 = 0"

For a required quadratic equation of $\bf{ax^2 + bx + c = 0}$ the solutions for which can be represented by the quadratic formula of :

$\boxed{\bf{x_{1, \: 2} = \dfrac{- b +- \sqrt{b^2 - 4ac}}{2a}}}$

Here, a = 5,  b = - 8,  c = - 4.

Solving for positive and negative values respectively:

$\bf{x_{1} = \dfrac{- (- 8) + \sqrt{(- 8)^2 - 4(5)(- 4)}}{2(5)}}$

$\bf{x_{1} = \dfrac{8 + \sqrt{64 + 80}}{2 \times 5}}$

$\bf{x_{1} = \dfrac{8 + \sqrt{144}}{2 \times 5}}$

$\bf{x_{1} = \dfrac{8 + \sqrt{144}}{10}}$

$\bf{x_{1} = \dfrac{8 + 12}{10}}$

$\bf{x_{1} = \dfrac{20}{10}}$

$\bf{\therefore \quad x_{1} = 2}$

For the second solution in negative form of equation:

$\bf{x_{2} = \dfrac{- (- 8) - \sqrt{(- 8)^2 - 4(5)(- 4)}}{2(5)}}$

$\bf{x_{2} = \dfrac{8 - \sqrt{64 + 80}}{2 \times 5}}$

$\bf{x_{2} = \dfrac{8 - \sqrt{144}}{2 \times 5}}$

$\bf{x_{2} = \dfrac{8 - \sqrt{144}}{10}}$

$\bf{x_{2} = \dfrac{8 - 12}{10}}$

$\bf{x_{2} = \dfrac{- 4}{10}}$

$\bf{\therefore \quad x_{2} = - \dfrac{2}{5}}$

Therefore the final solutions for this quadratic equations are:

$\boxed{\underline{\bf{x_{1} = 2}}}$

$\boxed{\underline{\bf{x_{2} = - \dfrac{2}{5}}}}$

Hope this helps you and solves the doubts for getting the equation solved by quadratic method!